PALACHE AND WOOD. — CRYSTALLOGRAPHIC NOTES. 645 



faces on crystals of different habits. Were the form not already known, 

 it would not be recognized on the evidence furnished by this suite. 



h (210). This form was present on all twelve crystals. It is uni- 

 formly good in quality with bright faces very little striated. On the 

 prismatic habit its faces are necessarily very narrow, but they are defi- 

 nite and of excellent quality. It is the dominant prism on Chester 

 diaspore. 



m (110). Only five faces of this form were observed, all on crystals 

 of the prismatic habit. Therefore all the faces were very narrow. 

 They varied in quality from very good to very poor, but they were 

 definite and placed close to the calculated position. 



k (230). Seven faces of this form were observed, all on crystals 

 of the prismatic habit. The faces are good, unstriated, and well 

 placed. 



1 (120). Eleven faces of this form were found. It was not confined 

 to any habit, but occurred on all types. It was better developed on the 

 slender prismatic crystals. Sometimes it is badly striated, but again it 

 is found with bright clear faces. 



e (Oil). Ten faces of this dome were seen. It occurs on all types 

 of the Chester crystals. It is seldom quite good, being usually the 

 centre point of a zone of striations. For this reason the readings in 

 azimuth were often slightly displaced. While sometimes dull, it is 

 usually sharp and bright, but sometimes very small. 



w (101). One disturbed, doubtful face lay approximately in the 

 position of this form. The form is established or no mention of the 

 observation would be made. 



p (111). Nine faces of this form were observed distributed among 

 all three habits. But it finds its best development on the disc-like 

 type where occasionally it is comparatively large and usually sharp and 

 good. The prismatic habit furnished only one of these readings, but in 

 that case the face was quite definite. 



*s (212). This form was well developed on ten crystals. It is the 

 dominant pyramid on the Chester diaspore. It is always sharp and 

 sometimes of comparatively good size, but in some of the disc-like crys- 

 tals its faces are not so large as those of the pyramid p. 



q (232). Two faces, both doubtful, one each on two different crys- 

 tals (one prismatic, the other disc-like), are all the evidence the Chester 

 suite presents of the development of this form. 



x (133). Eight faces of good average quality, fairly well placed 

 and confined to the prismatic habit, establish this form on the Chester 

 species. Most of the faces are well defined but small. 



v (122). Seven faces of poor quality on three crystals of habits a 



